Pyridotriazole brighteners



3,049,438 PYRIDOTRIAZOLE BRKGHTENER Bennett G. Buell, Somerville, and Robert S. Long, Bound Brook, N.J., assignors to American Cyanamid Company, New York, N .Y., a corporation of Maine No Drawing. Original application Nov. 26, 1957, Ser. No. 698,930. Divided and this application Nov. 3, 1958, Ser. No. 771,175

6 Claims. (Cl. 117-335) This invention relates to organic fibers treated with compounds of the structure:

in which Y may be hydrogen, alkyl, halogen, carboxy,

carbalkoxy or carboxamido, It may be one or two and R is an organic radical having a 6-mernbered aromatic ring directly bonded to the triazole rings, the said group R being the residue of a diazotizable amine. Certain new classes of compounds of different structures which may be used to brighten organic fibers to form our invention belong to the groups of compounds listed below:

amino, acylamino, carboxy or phenyl, R may be hydrogen, alkyl or halogen, one of R and R not being hydrogen, and Y being defined as above in this and each succeeding formula, and quaternary salts thereof.

N-M HEN \N N/ in which M is a naphthalene ring which may carry halogen, alkyl, alkoxy and sulfo groups, and quaternary salts thereof.

N-- CH=CH Z H NENI l N X W in which X may be hydrogen, sulfo or cyano; W may be 3,049,438 Patented Aug. 14, 1962 hydrogen or sulfo and Z may be hydrogen, sulfo, amino or substituted amino, and quaternary salts thereof.

in which Q may be 0, NH or S; U may be hydrogen or methyl and T may be hydrogen or suite, and quaternary salts thereof.

Y /N N \g M HEN A in which Q may be 0, NH or S; and V may be hydrogen, alkyl, or aryl, and quaternary salts thereof.

Y A fivx -QO t HzN \N/ \Nl NH:

in which the biphenyl moiety may carry one sulfonic acid group ortho to the biphenyl bond, and quaternary salts thereof.

in which D and E may be hydrogen or sulfo, and quaternary salts thereof.

in which F may be hydrogen or lower alkyl, and quaternary salts thereof.

and quaternary salts thereof.

and quaternary salts thereof.

(11) Y N N K in which K and K may be hydrogen or sulfo, and quaternary salts thereof.

in which L may be hydrogen, methyl, methoxyl, or chloro, and quaternary salts thereof.

in which B is a S-pyrimidyl radical, and quaternary salts thereof.

NONH G1 in which G and G can be the residue of an aliphatic amine such as ethanolamine or diethanolamine or of an aromatic amine or aminosulfonic acid, and quaternary salts thereof.

Optical bleaching agents or brighteners are widely used in whitening and brightening textile fibers of various types and are used both during the manufacture of textiles and during the operation of laundering fabrics. When optical bleaching agents or brighteners are applied to cloth, the blue fluorescence of the brightener, excited by ultraviolet, irradiation acts to neutralize the yellowish color of the cloth, producing a whitening and brightening effect. A necessary property is substantivity on the cloth. Brighteners are applied from very dilute solution, and unless they are substantive on the cloth, and thus are not readily washed off, the effect will not be achieved. Various types of compounds are used as brighteners and no brightener is equally substantive on all fibers. Most brighteners are relatively non-substantive to one or another fiber, and consequently, different types of brighteners must be used for different types of fabrics. Compounds which are suitable for cellulose fibers such as cotton, are often not usable for synthetic fibers such as polyacrylonitriles or superpoly amides. Brighteners which show substantivity on most common textiles are a great need in the industry. While it is possible that no single brightener will ever be completely universal in its application, extensive research has been done in the search for at least a class of compounds which will be readily usable on any fiber or which will include members approaching universality of application.

The fluorescence of brighteners usually ceases immediately upon the removal of the source of ultraviolet light. Phosphorescence, or the continuation of emission of visible light for an appreciable time after removal of the ultraviolet source, is not a necessary characteristic for a brightenen' However, phosphorescence is a property which is usable in other ways and whose importance is rapidly increasing. A particularly important application for phosphorescent compounds is described in the copending application of Eugene Allen, Serial No. 644,846, filed March 8, 1957, now Patent No. 2,914,083, where the phosphorescent property is used for the purpose of Weft straightening." This is a process in the textile field for maintaining fill threads perpendicular to warped threads and selvages. The phosphorescent effect allows control through the use of photocells which are activated by the difference in the period of light emission by fluorescent compounds which phosphoresce, and those which do not. It is necessary to use phosphorescent compounds in such weft straightening because of the almost universal use of brighteners in the finishing of cloth. Heretofore the control was through the fluorescence of a thread dyed specially with a brightener, but now, with all threads being dyed with brighteners, the machine will not operate satisfactorily. Consequently, as described by Allen in his specification, the control is now carried out by dyeing the control threads With a phosphorescent brightener, which thus continues emitting light after the source of ultraviolet is removed.

For use in such an application, a compound must possess other properties besides fluorescence and phosphorescence. It is necessary that the compound be stable to various chemical and physical treatments when applied to the fiber or a fabric Without losing the phosphorescent property and without being removed from the fiber or the fabric. Most compounds, even when they show some phosphorescence, do not withstand the harsh treatment necessary in the finishing of fabrics. Such treat ment includes caustic solution at elevated temperatures, bleaching with hydrogen peroxide, steaming, and the like. There is thus a further need for a class of compounds which will phosphoresce and also which will be stable under the harsh treatments of textile manufacture.

We have found that organic fibers can be brightened readily with compounds of the formula:

in which Y may be hydrogen, alkyl, halogen, carboxy, carbalkoxy or carboxamido; It may be 1 or 2, and R is an organic radical having a 6-mernbered aromatic ring directly bonded to the triazole rings, the said group R being the residue of a diazotizable amine, and that such organic fibers exhibit phosphorescence and fluorescence and are stable to the various conditions of textile manufacture. We have further found that these brighteners can be applied to a great variety of fibers, many of them being applicable to a greater or lesser extent to nearly all organic fibers and that, with variations in the structure, it is possible to increase the substantivity of such compounds on specific classes of organic fibers. We have further found several distinct classes of new compounds as listed above, which form a separate aspect of our invention, as claimed in our copending application Serial No. 698,930, filed November 26, 1957, of which this is a division. These classes of compounds are not equivaa lent, their substantivity on various fibers, their color, their phosphorescence and their stability to various treatments varying from group to group.

It is an advantage of our invention that by proper selection of substituents, it is possible to brighten a wide range of organic fibers. It is known that brighteners tend to be substantive on cellulosic fibers when they are linear coplanar molecules having extended conjugation. It is surprising however, that the compounds used in our invention go on cellulosic fibers even when these structural characteristics are not prominent. Thus, 2-phenyl-6- amino-2,3-pyridotriazole is substantive on cotton, although it is not an extended linear coplanar molecule, nor is it sulfonated. However, when the substituent on the triazole ring is a simple aryl group, one obtains optimum brightening only on polyacrylonitrile fibers. Cotton brightening is obtained more readily with the use of more complicated substituents on the triazole ring or, better yet, even bis-triazoles. It is a further advantage of our invention that one readily obtains good acid solubility with pyridotriazoles, as contrasted to benzoor naphthotriazoles. It is a further advantage of our invention that the pyridotriazoles have good affinity to many kinds of synthetic fibers, especially polyamides and polyacrylonitriles. It is a still further advantage of our invention that the pyridine ring in the pyridotriazole nucleus can be quaternized with the result that increased solubility is obtained and affinity is obtained on polyacrylonitrile fibers at a wide range of pHs.

In the preparation of compounds substantive to particular fibers, attention must be given to such factors as the type of fiber to be treated, the method of application (and the solubility properties), Whether the desired effect is phosphorescence of fluorescence (and if fiuoroescence, whether reddish-blue or greenish-blue) and similar factors. When solubility in Water is important, sulfonated aryl residues can be used. However, sulfonation has the effect of decreasing aifinity on polyacrylonitrile fibers and similar non-cellulosic fibers. Greener shades of fluorescence can be attained by using suitable auxochromic substituents such as alkoxyl, dialkylamino or acylamino. One of the mose useful and at the same time most unexpected advantages of the present invention is the Wide variety of efiects which can thus be built into the products by proper selection of the starting materials.

The dyestuffs used in the present invention are convem'ently prepared by coupling an aromatic diazonium compound with a 2,6-diaminopyridine to form a S-arylazo-2,6-diaminopyridine, which is then triazolized by an oxidative ring closure method using a mild oxidizing agent. If it is desired to quaternize, this is achieved by reaction of the triazole product with an alkylating agent such as an alkyl halide. Various aromatic amines may be used to form the diazo component in the first step of this preparation and proper selection of the amine makes it possible to produce an optical bleaching agent with properties making it suitable for use on various textile fibers. Examples of diazotizable amines which may be used in the reaction to produce compounds of the invention are:

Aniline pand m-Aminobenzoic acid Alkyl and aryl pand m-aminobenzoates pand m-Aminobenzenesulfonic acid and their alkyl and aryl esters pand m-Aminobenzenealkyl sulfones pand m-Aminoacetanilide pand m-Aminobenzanilide pand m-Aminoanisanilide pand m-Aminobutyranilide pand m-Toluidine pand m-Chloroaniline pand m-Bromoaniline pand m- Fluoroaniline o-Xylidine (3,4-dirnethylaniline) pand m-Anisidine pand m-Nitroaniline 4-aminobiphenyl Benzidine 4-aminostilbene 4,4-diaminostilbene-2,2-disulfonic acid Z-naphthylamine 2-aminonaphthalene-6-sulfonic acid Z-aminonaphthalene-S-sulfonic acid 2-aminonaphthalene-S,7-disulfonic acid 2-aminonaphthalene-6,8-disulfonic acid Z-(p-aminophenyl)-benzimidazole, benzoxazole and ben- Zothiazole 5- and 6-aminobenzoxazole, -benzothiazole, -benzimidazole, benzotriazole 4-aminopyridine 3-aminopyridine 6-methoXy-2-naphthylamine 6-chloro-2-naphthylamine These diazos are coupled with various 2,6-diaminopyridines such as the following:

2,6-diaminopyridine 2,6-diamino-3-methylpyridine 2,6-diamino-4-methylpyridine 2,6-diaminopyridine-4-carboxylic acid and its esters 2,6-diamino-3-bromopyridine 2,6-diamino-4 bromopyridine 2,6-diaminopyridine-4-carboxamide The 3-arylazo-2,6-diaminopyridine intermediate is then oxadized with a mild oxidizing agent such as air in the presence of copper sulfate, which results in ring closure to the triazole derivative.

Pyridotriazoles in which the substituent on the triazole ring is para-aminophenyl radical forms an especially useful class of compounds for use in our invention, since they can be intermediates for the further preparation of more complicated brighteners and phosphorescent agents which can also be used in our invention. For example, the amino group on this phenyl ring can be diazotized and coupled into other coupling components and, when the coupling component is so constituted that an o-aminoazo compound is formed, this too can be triazolized to give a his or poly-triazole derivative. Thus, a bis-triazolo compound, either symmetrical or unsymmetrical is readily produced. The symmetrical bis-triazolo compounds are also readily produced from tetrazotization of an aromatic diamine.

The fibers which may be used in our invention include the various organic fibers used in the textile industry, both synthetic and natural, since substantivity and other properties can be varied by the choice of the proper substitucuts and the proper ring groupings in the brightener molecule to favor substantivity on any particular type of fiber. Among the fibers which may be used are the natural fibers, both cellulosic and non-cellulosic, such as cotton, wool, silk, and the like, and the synthetic fibers of both the cellulosic and non-cellulosic types such as viscose rayon (i.e., regenerated cellulose) cellulose esters such as cellulose acetate, polyacrylonitrile (either the homopolymer or copolymers with various comonomers such as vinyl pyridine, methyl acrylate, vinyl chloride, and the like), superpolyamides such as hexamethylene polyadipamide and poly-omega-aminocaproamide, and superpolyesters such as polymeric glycolterephthalate.

The brighteners to be used in our invention are especially useful on those-fibers for which most known brighteners have been not satisfactory, such as the polyacrylics and the superpolyesters.

The brighteners may be applied as optical bleaching agents or as phosphorescent agents from detergent compositions as ordinarily formulated in the art, or from rins ing liquors for treatment during textile manufacture or after laundering operations.

In addition to being useful as brightening agents, the

products used in the preparation of our invention are also phosphorescent and thus the fibers of our invention can be used where phosphorescence is important for special efiects. 2-phenyl-6-amino-pyridotriazole is especially useful for this purpose because of its phosphorescence and its substantivity to a wide variety of fibers. A particularly important application for such phosphorescent fibers is described in the copending application of Eugene Allen Serial No. 644,846, filed March 8, 1957, Where the phosphorescence property is utilized for the purpose of weft straightening, a process in the textile field for maintaining fill threads perpendicular to warp threads and selvages. As described above, it is necessary for such application to have compounds which will stand rather drastic treatment. It is an advantage of the fibers of our invention that they are able to withstand the treatment with caustic solution at elevated temperatures and similar drastic treatments, and that they show suflicient phosphorescence.

Our invention includes not only organic fibers treated with a broad class of pyridotriazole compounds, but also specific groups falling within this broad class of compounds which have distinct and separate properties. These are all prepared in the same manner as described in general for the class, i.e., by the coupling of an aromatic diazo compound into a 2,6diaminopyridine. Thus, in each class the pyridines which may be used as the starting material are the same, but the diazotizable amine which is used varies with the class of compounds being considered.

In the class of compounds of the structure:

Y N W i zN- the amino compounds which may be used as starting materials include p-Chloraniline p-Toluidine p-Anisidine p-Phenetidine p-Nitroaniline p-Phenylenediamine Monoacylated p-phenylenediamines; such as p-acetamidoaniline p-Benzamidoaniline p-Propionylamidoaniline, and the like p-Aminobenzoic acid 8 2 aminonaphthalene 4,8 disulfonic acid, 6 methoxy- Z-naphthylamine, 6-chloro-2-naphthylamine, and the like.

The amines which can be used to prepare the compounds of the structure:

U N CH=CH Z EN Y N C/ U Q \lj include dehydrothiotoluidine, dehydrothiotoluidine sulfonic acid, 4-amino-2-phenyl benzoxazole, 4'-amino-2- phenyl-benzimidazole, and the like.

In the preparation of compounds of the class:

HZN N/ the following amines may be used; 5- or 6-aminobenzothiazole, Z-methyl-S- or 6-aminobenzothiazole, Z-phenyl- 5- or G-aminobenzothiazole, 5- or 6-aminobenzoxoazole, 2-pheny1-5- or 6-aminobenzoxoazole, Z-methyl-S- or 6- aminobenzoxoazoles, S-aminobenzimidazole, 2-methyl-5- (6) -aminobenzimidazole, 2phenyl-5 6) -aminobenzimidazole, and the like.

In the preparation of compounds of the structure:

HQN N/ /\Ny NHI the starting material which is used as the diazotizable amine may be benzidine or a benzidine monosulfonic acid in which the sulfonic acid group is ortho to the biphenyl bond.

4-aminodiphenyl Compounds of the type:

HQN N11, N D n N N 4-chlor-3-methylaniline 4-bromo-3-ethylaniline 4-chlor-3-butylaniline 3,4-dichloroaniline 3-chlor-p-anisidine m-Bromaniline, and the like The amines which may be used to prepare compounds of the class of the structure:

\NM HzN \N/I\\N/ include beta-naphthylamine, 2-aminonaphthalene-6-sulfonic acid, Z-aminonaphthalene-S-sulfonic acid, 2-aminonaphthalene-4,6-disulfonic acid, 2-aminonaphthalene-5,7-

can be prepared starting with such compounds as 4,4-

HiN

disulfonic acid, Z-aminonaphthalene-6,8-disulfonic acid, diaminodiphenylamine, 4,4 diaminodiphenyl methyl 9 amine, 4,4'-diaminodiphenyl ethyl amine, 4,4'-diaminodiphenyl butyl amine, and the like.

The starting material for compounds of the structure:

is 3,7-diamino-dibenzothiophene-S,5'-dioxide.

Compounds of the formula:

are prepared from 4,4-diamino-N,N-diphenylurea.

Compounds of the structure:

are prepared by starting with either pa-ra-nitroaniline for the first coupling into the 2,6-diaminopyridine derivative or similarly from anacylaminoaniline. After this first coupling, either the nitro group is reduced or the acyl group is hydrolyzed and the freed amino group is then diaz'otized and coupled into :a naphthylamine, followed by tri-azolization. The naphthylamine can be Z-naphthylamine, 2 naphthyl-aminel-sulfonic acid, 2 naphthylamine-S-sulfonic acid, naphthionic acid, Laurents acid, 2-naphthylamine-6-sulfonic acid, 2-naphthylamine-5-sultonic acid, 2-naphthylarnine-4,6-, 5,7- or 6,8-disulfonic acid, 6 -methoXy-2-naphthylamine, 6-chloro-2-uaplrthylamine, and the like.

The compound of the structure:

in which L may be hydrogen, methyl, methoxyl, or chloro, are similarly prepared by a second diazotization and coupling and triazolization, this time by coupling into 6-iamino-5-substituted 2-para-sulfophenyl benzotriazole and performing a second niazolization. The substituent on the coupling component for the second triazolization can be hydrogen, methyl, methoxyl or chloro.

Compounds of the type:

in which E is a -pyrimidyl nucleus are obtained by coupling a diazotized amino pyrimidine into a 2,6-diamino pyridine and triazolizing. For this purpose one can use S-amino pyrimidine, substituted S-amino pyrimidines, and the like.

156 Compounds of the type:

H2N\N \N/ N N are prepared by reacting the intermediate 2-p-aminophyenyl-G-amino-pyridotriazole with cyanuric chloride,

followed by further reaction of the product with aliphatic amines such as alkyl amines or preferably substituted alkyl-amines (ethanolamine, diethanolamine, morpholine, etc.) or with aromatic amines or aminosulfonic acids such as aniline, sulianilic acid, and the like. 5 In all these various classes of brighteners, as well as in the principal invention of the brightened fibers, the pyridine ring in the pyridotriazole moiety can be quaternized by treatment with an alkylating agent to form a quaternary compound on the pyridine ring nitrogen. Examples of allcylating agents which may be used are methyl iodide, ethyl bromide, butyl bromide, benzyl bromide, dimethyl sulfate, diethyl sulfate, ethylene chlorohydri-n, beta-diethylamino ethyl chloride, alkyl tosylates such as methyl tosyl-ate, and the like. Among the purposes of such quaternization are to get increased Water solubility of the brightener molecule and to permit the application oi the dyestuff over a broader range of pH. The quaternized brighteners are in general equivalent to the unquaternized brighteners, and in some cases superior, in substantivity to various fibers. Consequently, the quaternized compounds and the fibers dyed with them form a part of our invention.

Our invention can be illustrated by the following examples in which parts are by weight unless otherwise indicated.

Example 1 A mixture of 27.9 parts of 2,6-diamino-3-phenylazopyridine (commercially available as Pyridium or Azoimide"), 450 .parts of ethanol, parts of water and 180 parts of concentrated ammonium hydroxide is heated under reflux with stirring. A hot solution of 170 parts of copper sulfate in 500 parts of water and 300 parts of concentrated ammonium hydroxide is added. After heating for several hours, an additional portion of 25 parts of copper sulfate parts of water and 45 parts of concentrated ammonium hydroxide is added and heating is continued until the reaction is substantially complete, as shown by disappearance of the starting material. After cooling the mixture, the product is removed by filtration and washed thoroughly with dilute ammonium hydroxide and water to remove the copper. The product is purified by dissolving in 400 parts of water, 450 parts of ethyl alcohol, and parts of concentrated hydrochloric acid. Aiter treatment with a decolo'rizing agent and filtering, the filtrate is treated with 55 parts of concentrated hydrochloric acid. On cooling, the hydrochloride of the product separates as a cream-colored 75 rod and is removed by filtration and washed with alcohol.

Example 2 WN\ -CH I st Qt?" Q A diazonium solution is prepared from 2.75 parts of 4-amiuo-stilbene-2-sulfonic acid by diazotization with sodium nitrite. The diazonium solution is combined with a solution of 1.09 parts of 2,6-diaminopyridine in 75 parts of acetic acid, 50 parts of water and 2.2 parts of concentrated hydrochloric acid. With stirring, 50 parts of a saturated solution of sodium acetate is added slowly and stirring is continued until coupling is complete. The solid aminoazo compound is removed by filtration and washed with water and is then taken up in 90 parts of 95% ethanol, 22 parts of concentrated ammonium hydroxide and 20 parts of water. The mixture is heated to the boiling point and a hot solution of 17 parts of copper sulfate, 75 parts of Water, and 36 parts of concentrated ammonium hydroxide is added and the mixture is heated at the reflux temperature with stirring until the reaction is complete. After the mixture is cooled, the solid is removed by filtration, slurried in dilute hydrochloric acid and then again isolated by filtration. For purification, it is dissolved in methyl cellosolve containing a small amount of sodium hydroxide and after clarification with a decolorizing agent, the product is isolated from the filtrate by adding additional sodium hydroxide solution and saturated sodium acetate. After stirring, the product is isolated as a light tan sodium salt.

Example 3 The procedure of Example 2 is followed, except that an equivalent quantity of sulfanilic acid is substituted for the 4-aminostilbene-2-sulfonic acid. The product is obtained as an almost White sodium salt.

Example 4 A diazonium solution is prepared by diazotizing 3.38 parts of 4-aminobipheny1 with sodium nitrite in acetic acid at 30 C. The diazonium solution is combined with a solution of 2.18 parts of 2,6-diaminopyridine in 100 parts of acetic acid, 100 parts of water, and 4 parts of concentrated hydrochloric acid. With stirring, 75 parts of saturated sodium acetate solution is added. The mixture is stirred until the coupling is complete and the light orange cupling product is removed by filtration and triazolized by oxidation with copper sulfate and ammonium hydroxide as described in Example 2. The product is purified by dissolving in about 600 parts of hot methyl cellosolve and excess concentrated hydrochloric acid, clarifying with a dccolorizing agent and isolating by the addition of 300 parts of water and excess ammonium hydroxide to the filtrate.

Example 5 an equivalent quantity of 2,6-diamino-3-bromopyridine is used in place of the 2,6-diaminopyridine and an equivalent quantity of aniline is used in place of the 4-aminobiphenyl. The corresponding methyl compound is prepared by starting with 2,6-diamino-3-methylpyridine.

Example 6 l GD The procedure of Example 4 is followed except that an equivalent quantity of 2,6-diamino-4-picoline is used in place of the 2,6-diamiuopyridine.

Example 7 A diazonium solution is prepared by diazotizing 13.8 parts of 4-nitro-aniline with sodium nitrite. The solution is combined with a solution of 10.9 parts of 2,6-diaminopyridine in 500 parts of acetic acid, 500 parts of water and 18 parts of concentrated hydrochloric acid. With stirring, the mixture is neutralized with saturated sodium acetate solution and the bright red o-aminoazo product which forms is removed by filtration and washed with water. This o-aminoazo product is taken up in 540 parts of ethanol, 150 parts of water, and parts of concentrated ammonium hydroxide. The mixture is heated and a hot solution of 125 parts of copper sulfate, 500 parts of water, and 225 parts of ammonium hydroxide is added. The mixture is heated at the reflux temperature until the triazolization is complete, cooled, and the product is removed by filtration. This nitro compound is then reduced to the corresponding amino compound by the following procedure:

The nitro compound is added to parts of water, 45 parts of ethanol and 120 parts of 5 N sodium hydroxide. To the mixture at 70-85 C. is added 70 parts of sodium hydrosulfite. After stirring and cooling, the product is isolated by filtration and washed alkali-free with water. The amino compound is purified by clarification with a decolorizing agent from solution in 250 parts of hot 4 N hydrochloric acid, and isolated by making the filtrate alkaline by the addition of ammonium hydroxide.

Example 8 To 0.75 part of 6-amino-2-(p-aminophenyl)-2-pyrido [2,3-d]-v-triazole (prepared as in example 7) is added 25 parts of pyridine and 0.7 part of p-anisoyl chloride. The mixture is heated at the reflux temperature for a short time and is then drowned in ice. The solid product which forms is removed by filtration and washed with water and is purified by recrystallization from methyl cellosolve, giving the product in the form of prisms with a melting point of 293296 C.

By the use of equivalent amounts of other acyl halides in place of the p-anisoyl chloride such as acetyl chloride, butyryl chloride, stearyl chloride, benzoyl chloride, 2,4- dichlorobenzoyl chloride, and similar compounds, the corresponding acylamide compounds are obtained.

1 3 Example 9 A diazonium solution prepared by diazotizing 2.26 parts of 6 amino-Z-(parninophenyl)-2-pyrido[2,3-d]-vtriazole (prepared as in Example 7) is combined with a slurry of 2.54 parts of sodium naphthionate in 100 parts of water, 4 parts of hydrochloric acid and 50 parts of acetic acid. With stirring, 50 parts of saturated sodium acetate solution is added and the stirring is continued until the coupling is complete (4 hours). The o-aminoazo product is removed by filtration and triazolized by oxidation using the procedure described in Example 7. Purification of this bis-triazolyl product is eitected by dissolving the product in 400 parts of hot m'onoethauolamine, and 4 parts of N sodium hydroxide solution. After clarification wth a decolorizing agent, 100 parts of water is added to the filtrate and the sodium salt of the product is salted out by the addition of sodium hydroxide, giving a crystalline yellow product.

Example 10 A tetrazonium solution prepared by tetrazotizing 1.86 parts of benzidine in 100 parts of Water, 9 parts of hydrochloric acid and 8 parts of 1 N sodium nitrite solution is combined with a solution of 2.4 parts of 2,6-diaminopyridine in 100 parts of Water and 5 parts of concentrated hydrochloric acid. The mixture is neutralized to Congo red indicator by addition of saturated sodium acetate solution (about 60 parts). The color changes from blueblack to dull orange. After stirring the mixture, the solid azo product i removed by filtration.

For conversion to the triazole derivative the disazo product from above is slurried in a hot mixture of 150 parts of pyridine and 20 parts of concentrated ammonia. A half-portion of a solution of 24 parts of copper sulfate, 100 parts of water and 40 parts of ammonia is added and the mixture is heated for several hours. The other half of the copper sulfate solution is then added and the mixture is heated until the reaction is complete. The solid material is removed by filtration and purified by recrystallization from about 300 parts of N-methyl-2- pyrrolidone.

Example 11 and after stirring, the solid disazo compound is removed by filtration and triazolized by the procedure described below.

The solid product is dissolved in a hot mixture of 150 parts of pyridine and 20 parts of ammonium hydroxide. To this is added a half portion of a solution of 24 g. copper sulfate, 100 parts of Water and 20 parts of concentrated ammonia. After heating a short period, the second half portion of the copper sulfate solution is added and the mixture is heated until the reaction is complete. The solid bis-triazolo compound is removed by filtration.

The product may be purified by recrystallizing from hot dimethyl formamide containing a small amount of caustic and then precipitating the product from the cooled d i methylformamide filtrate by addition of water and hydrochloric acid to the neutral point.

Example 12 CH3 \NQN/ Hm NA N A diazonium solution prepared by diazotization of 2.26 parts of 6-amino-2- (p-aminophenyl) -2-pyrido [2,3-d] -vtriazole with sodium nitrite in hydrochloric acid solution is combined with a solution of 3.04 parts of 6-arnino-2H- 5-methyl-2-(p-sulfophenyl)-benz0triazole in 160 parts of acetone, 100 parts of water and 4 parts of concentrated hydrochloric acid. With stirring, 50 parts of saturated sodium acetate solution is added and the mixture is then stirred until the coupling is complete (4 hours). The resulting o-aminoazo product is removed by filtration and then triazolized by ozidation with copper sulfate using the procedure described in Example 6. The product is isolated as the sodium salt and purified by treatment with decolorizing charcoal in hot dimethyl formamide solution, giving the product as the purified sodium salt.

Example 13 C O OH The procedure of Example 1 is followed except that an equivalent amount of 2,6-diaminopyridine-4-carboxylic acid is used in place of the 2,6-diaminopyridine.

A tetrazoniurn solution is prepared by tetrazotizing 37 parts of 4,4'-diarninostilbene-2,2'-disulfonic acid. This is done by first dissolving the stilbene derivative in 15 0 parts of water and 7 parts of 5 N sodium hydroxide solution. T Wenty-one parts of 1 N sodium nitrite solution is added and after filtering, the solution is poured into a mixture of 200 parts of ice and 16 parts of hydrochloric acid. After stirring for a short period, the excess nitrite is destroyed with sulfamic acid.

To the above brown slurry is added a solution of 2.4 parts of 2,6-diamino-pyridine in 150 parts of Water and 5 parts of concentrated hydrochloric acid. Saturated sodium acetate solution is added until the mixture is neu- Example 14 tral to Congo red indicator. Coupling takes place rapidly zoic acid,

15 I 16 Example 15 Example 19 H N HZN 2 \N N H, N N (N 0 a The procedure of Example 4 is followed using an equiv- To a hot well-stirred solution of 22.9 parts of the soalent quantity of 3,4-dimethylaniline in place of the 4- dium salt of benzaldehyde ortho sulfonic acid and 16.2 aminobiphenyl. Similarly, other substituted products are parts of S-nitro-orthotoluonitrile in 40 parts of pyridine obtained if one uses 3-chloro-4-methylaniline or 4-chlorothere is added 2 parts of piperidine and 9.2 parts of sodium 3-methy1aniline in place of the dimethylaniline. bicarbonate. The mixture is heated on a steam bath until the reaction is substantially complete. During the heating Example 16 period, an additional 40 parts of pyridine is added. The N mixture is then diluted with 200 parts of Water and the pyridine is stripped outwith steam. The mixture is cooled with ice and the precipidated product is isolated by filtra- H N \N tion and dried.

N To a vigorously stirred mixture of 29.5 parts of iron powder, 150 parts of water and 4 parts of glacial acetic acid heated under reflux there is gradually added 11.8 parts of the product of the preceding paragraph. The mixture is heated under reflux with good stirring until the reaction is substantially complete and then is neutralized with a small excess of soda ash. The iron sludge is filtered and washed with hot methanol and the filtrate and washings are treated hot with charcoal. The mixture Example 17 is filtered and the filtrate is acidified with concentrated hydrochloric acid. The precipitated 4-amino-2-cyanostil- N bene-2'-sulfonic acid is isolated by filtration and purified NQGH=CH by recrystallization from alcoholic methanol followed by HBN X \N/ The procedure of Example 4 is followed using an equivalent quantity of beta-naphthylamine in place of the 4- aminobiphenyl. Corresponding substituted compounds are obtained by using such derivatives as Bronners acid, Dahls acid, amino J acid and amino G acid in place of beta-naphthylamine.

reprecipitation with hydrochloric acid.

An equivalent quantity of the above product is used in the procedure of Example 2 in place of the 4-aminostil- The procedure of Example 4 is followed using 4-am1nobene 2 su1 fonic acid used in that example.

stilbene in equivalent quantities in place of the 4-aminobiphenyl. The product is a good brightener for nylon. Example 20 N CH=OH@NH CO H N \N N SO H SO H Example 18 The procedure of Example 2 is followed using an equivalent quantity of 4-amino-4-nitrostilbene-2,2'-disulfonic acid. The nitro group is then reduced and acylated as in N i CH=GH Example 8, using benzoyl chloride. HnN

Example 21 A mixture of 30 parts of 2-cyano-4-nitrotoluene, 22 parts of benzaldehyde and 5 parts of piperidine is heated Q at 125-140 C. until the reaction is substantially com- Hm CH3 plete. The melt is dissolved in 160 parts of hot glacial N S acetic acid and on cooling the crystalline solid which forms is filtereda boiling Suspension of Parts of The procedure of Example 4 is followed using an equivthe above Product 250 Parts of 95% added a alent quantity of dehydrothioparatoluidine in place of the Solutlon 0f 44 Parts of hydrated 542111119115 chlorldff and Laminodiphenyl. A sulfonated derivative of the above parts of concentrated hydrochloric acid. The mixture 15 product is prepared by following h procedure of E heated at reflux temperature until reduction is substanample 2 d t ting with an equivalent quantity of dehytlany complete- The mlxmre 15 then Cooled and the Solid drothioparatoluidine sulfonic acid in place of the aminois removed by filtration. It is purified by slurrying in stilbene lfo j acid dilute sodium hydroxide solution.

A solution of 4.4 parts of the 4-amino-2-cyano-stilbenes Example 22 so produced in 120 parts of acetic acid is prepared and to N it is added 8.4 parts of concentrated hydrochloric acid. Twenty-two parts of N/l sodium nitrite solution is then added with coohng, and after stirring for a short period HIN the excess nitrite is discharged by the addition of sulfamic N 0 acid. The diazo solution is then used to couple with a solution of 3 parts of 2,6-diaminopyridine in 100 parts of The procedure of Example 4 is followed using an equivacetic acid, 100 parts of water and 4 parts of concentrated alent quantity of 4-amino-2-phenylbenzoxazole in place hydrochloric acid by the procedure of Example 4. of the 4-aminodipheny1.

I 7 Example 23 The procedure of Example 4 is followed using an equivalent quantity of 4-amino-21phenylbenzamidazole in place of the 4-aminodiphenyl.

Example 24 ma HQN \N i The procedure of Example 4 is followed using G-amino- 2-phenylbenzoxazole in equivalent quantities in place of 4-aminodipheny1. If G-aminobenzoxazole or 6-amino-2- methylbenzoxazole is used in equivalent quantities the corresponding brightener compound is obtained.

The procedure of Example 4 is followed using an equivalent quantity of 5 (6) -amino-2-methylbenzimidazole in place of 4-aminodiphenyl.

Example 27 V (I -Q ll H N- NH: 7 \N/ soar: \NANy The procedure of Example 11 is followed using an equivalent quantity of benzidirie-Z-sulfonic acid in place of diaminostilbene disulfonic acid.

Example 28 The procedure of Example is followed using an 18 the benzidine. The corresponding monosulfonic acid is prepared if the procedure of Example 11 is followed with 4,4'-diaminostilbene monosulfonic acid.

The procedure of Example 10 is followed using an equivalent quantity of 4,4'-diaminodiphenylamine in place of the benzidine. The corresponding n-alkyl compounds are prepared if equivalent quanties of 4,4-diphenylmethylamine and 4,4'-diphenylbutylamine are used in place of the 4,4-diphenylamine above.

Example 30 The procedure of Example 10 is followed using an equivalent quantity of 3,8-diaminodibenzothiophine-S,5'- dioxide in place of the benzidine. The corresponding sulfonated products are prepared by following the procedure of Example 11 using as starting materials equivalent amounts of 3,8-diaminodibenzothiophine-5,5-dioxide-2,7- di-sulfonic acid or the corresponding rnonosulfonic acid.

Example 31 The procedure of Example 10 is followed using an 0 equivalent quantity of 4,4'-diaminodiphenylurea in place of the benzidine.

Example 32 SO H Example 33 A mixture of 1 part of 5-amino-2-phenyl-(2)-pyrido [2,3-d]-v-triazole (prepared as in Example 1), 40 parts equivalent quantity of. 4,4'-diaminostilben'e in place of of methanol and 44 parts of methyl iodide is heated at l9 the reflux temperature until the reaction is completed, and is then evaporated to dryness. The yellow solid which is obtained is purified by precipitating from a methanol solution by the addition of diethyl ether, giving one part of white solid product which is soluble in water. Similar quaternary derivatives are obtained by the use of ethyl bromide, butyl bromide, benzyl chloride, allyl bromide, and ethylene chlorohydrin in place of the methyl iodide, although the chlorides and bromides take a longer time to give complete reaction. In cases where the solubility properties of the product were not sufficiently high, improved characteristics may be obtained by metathetical exchange of the anion to form the corresponding acetate or nitrate or other salt.

Example 34 Example 35 Q' t... N

A mixture of 21 parts of -amino-2-phenyl-(2)-pyrido- [2,3-d]-v-triazole, 32 parts of methyl p-toluene-sulfonate and 100 parts of ethanol is heated at the reflux temperature until the reaction is complete. After cooling, the solid is removed by filtration giving a water-soluble product.

When the methyl p-toluene sulfonate is replaced by an equivalent amount of methyl p-bromobenzene sulfonate the corresponding p-bromobenzene sulfonate salt is obtained.

Example 36 The procedure of Example 33 is followed using the product of Example 6 instead of the product of Example 1. The product of the above structure shows more affinity for some fibers than does the product of Example 6 and on other fibers is equivalent to the unquaternized product.

Example 37 The diazonium solution from 0.03 mole of m-bromoaniline is combined with a chilled solution of 3.27 parts (0.03 mole) of 2,6-diaminopyridine in 225 parts of Water and 5 parts of concentrated hydrochloric acid. Twentyfive parts of a saturated solution of sodium acetate is added dropwise with stirring. The mixture is stirred un- 2O til the coupling is completed. An orange product is filtered and allowed to drain.

The product is taken up in 92 parts of ethanol, 16 parts of water, 45.8 parts by volume of concentrated ammonia and 10 parts of pyridine and the mixture is heated with stirring. A hot solution of 38.9 parts of copper sulfate in 115 parts of water and 68.7 parts by volume of concentrated ammonia is added, a stream of air is introduced, and the mixture is refluxed with stirring until the reaction is substantially complete. It is cooled and the product is filtered, washed with water and dilute ammonia, dissolved in hot dilute ethanolic hydrochloric acid, filtered hot with charcoal and filtered again. The clarified solution is left standing and gradually yields orange crystals. A hot dilute ethanolic solution of this product is clarified with charcoal made alkaline to phenolphthalein and treated with sodium hydrosulfite at the boil. A shiny yellow product is filtered and dried at 60 C.

To 40 parts by volume of concentrated sulfuric acid is added with stirring, 2.8 parts (0.04 mole) of finely ground sodium nitrite, keeping the temperature below 50 C. The resulting solution is cooled to 5 C., and a solution of 4.0 parts of 4-aminopyridine in 10 parts of glacial acetic acid is added dropwise at temperatures below 15 C. The mixture is stirred until diazotization is complete. The diazonium solution is combined with a solution of 0.04 mole of 2,6-diaminopyridine in 25 parts of glacial acetic acid at temperatures below 15 C. The brown solution is stirred until coupling is complete and then drowned on 30 parts of ice, and neutralized to pH of 7.8 with dilute caustic. The product is then filtered and dried and recrystallized from absolute metha- 1101.

The coupling product is added to a hot solution of 5.0 parts of copper sulfate, 12.5 parts of water and 25 parts of pyridine and the mixture is refluxed until the reaction is complete. It is then steam stripped to remove the pyridine, acidified, cooled and filtered. The orange product is dissolved in hot dilute acid, filtered and dilute caustic solution is added to precipitate the product. This is then dissolved in hot alcoholic HCl and precipitated with concentrated ammonia to insure removal of the copper ions. A cream colored product is filtered, washed with water, and dried at C.

Example 39 An 0.005% solution of the brightener of Example 1 is prepared by dissolving 1 part of the brightener in 1000 par-ts of dimethyl formamide at room temperature. This is then diluted with water containing a small amount of dispersing agent (Triton X-100) to the 0.005% concentration. This solution is used in the following procedure:

To a mixture of 98.5 parts of water and 1.5 parts of 10% acetic acid solution is added 50 parts of 0.005% brightener solution from above. A 5-part piece of polyacrylonitn'le fabric (Orlon) is added and the temperature is raised to the boiling point and held therefore about 30 minutes. The fabric is removed, rinsed in water and dried in the air. It is much whiter and brighter in appearance than a piece of the untreated Orlon fabric.

Example 40 An 0.005 solution of the brightener of Example 33 is prepared by dissolving 1 part of brightener in 1000 parts of boiling water and diluting with water to the 0.005% concentration.

To a mixture of 98.5 parts of water and 1.5 parts of 10% acetic acid solution is added 50 parts of the 0.005

brightener solution. To the resulting acetic acid solution of the brightener is then added a 5-part piece of Orlon fabric (polyacrylonitrile). The temperature is raised to the boiling point and held there for 30 minutes. The fabric is removed, rinsed in water and dried. It is much whiter and brighter in appearance than a piece of the untreated Orlon fabric.

Example 41 To a solution of 0.025 part of the product of Example 1 is added 0.5 part of sodium sulfate. A piece of cotton cloth weighing 5.0 parts is added and the dyebath is heated to 130 F. After 15 minutes, another 0.5 part of sodium sulfate is added and heating is continued for another 15 minutes. The cloth is then removed, rinsed at 80 F., and dried. The treated cloth is exposed to UV light in a darkroom. After removing the source of the UV light it is observed that the emission of visible light continues for a noticeable period of time.

The treated cloth is immersed in a '5 sodium hydroxide solution and steamed at one to two pounds pressure for 1% hours. The cloth is then rinsed and immersed in a bleaching solution formulated with hydrogen peroxide and sodium silicate, after which it is then steamed again at one to two pounds pressure for one hour. After rinsing in dilute acetic acid and water and then drying, the treated cloth is again exposed to UV light. After the removal of the source of the UV light, the emission of visible light continues for a noticeable period, showing that the phosphorescent property of the cloth is retained after the above finishing treatments, typical of those to which fabrics are subjected in manufacture.

Example 42 N v: HflN \N N The procedure of Example 38 is followed using an equivalent quantity of S-aminopyrimidine in place of the 4-aminopyridine. The product has the above formula.

We claim:

1. Organic fibers treated with compounds selected from the group consisting of (1) compounds of the structure:

idue of a diazotizable amine, and (2) quaternary salts of the first group.

22 2. Organic fibers treated with the compound of the formula:

3. Organic fibers treated with quaternary salts of the formula:

HzN

in which X is an anion and R is selected from lower alkyl and aralkyl.

4. Superpolyamide fibers treated with compounds selected from the group consisting of (1) compounds of the structure:

HZN \N \N/ J11 6. Cellulosic fibers treated with the compound of the formula:

HzN \N \N/ References Cited in the file of this patent UNITED STATES PATENTS 2,008,536 Wolf July 16, 1935 2,637,731 Vaughan May 5, 1953 2,684,966 Keller et a1 July 27, 1954 OTHER REFERENCES Charrier et al.: Gazz. Chim. Ital., vol. 68, pp. 640-651 193 8).

Chemical Abstracts, vol. 32, pp. 624647 (1938). (Abstract of Oharrier et al., Am. Chim. Farm. 1938, No. 1, pp. 9-17.)

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,049,438 August 14, 1962 Bennett 6. Buell et a1.

It is hereby certified that error appears in the above numbered pat ent requiring correction and that the said Letters Patent should read as corrected below.

Column 3 lines 2 to 9, the formula should appear as shown below instead of as in the patent:

same column 3, line 63, for "superpoly amides" read superpolyamides column 5, line 42, for "mose" read most column 9, line 45, for "compound" read compounds lines 46 to 55, the formula should appear as shown below instead of as in the patent:

aolumn ll line 60, for "cupling" read coupling column 13,

line 23, for wth" read with lines 40 and 75, for "red" mad Red column 18 line 14, for "quanties" read uantities lines 43 to 51 the formula should appear as shown low instead of as in the patent:

KK 2 50 a lumn 20, lines 22 to 25 the formula should appear as shown low instead of as in the patent:

Signed and sealed this 6th day of August 1963.

EAL)

test:

NEST W. SWIDER DAVID L. LADD testing Officer Commissioner of Patents 

1. ORGANIC FIBERS TREATED WITH COMPOUNDS SELECTED FROM THE GROUP CONSISTING OF (1) COMPOUNDS OF THE STRUCTURE: 